Method of producing a diode element



Feb. 5, 1957 r A. F. PITYO METHOD OF PRODUCING A DIODE ELEMENT FiledAug. 17, 1955 2 Sheets-Sheet 1 INVENTOR ALBERT F. Pmro ATTORNEY Feb. 5,1957 A. F. PlTYO 2,779,993

METHOD OF PRODUCING A DIODE ELEMENT Filed Aug. 17, 1955 2 Sheets-Sheet 2INVENTOR A L BERTF PITYO WWW ATTORNEY United States Patent 2,779,993METHOD OF PRODUCING A DIODE ELEMENT Albert F. Pityo, Paterson, N. .1.

Application August 17, 1953, Serial No. 374,502

13 Claims. (Cl. 29-155.5)

This invention relates to a method of producing a diode element or thelike.

An important object of the invention is to provide a method includingthe steps of feeding a wire to an anode, welding the wire to the anode,forming the wire to produce the whisker, and then severing the wire tocomplete the product, all steps being carried out in proper sequence.

A further object of the invention is to provide a method which willproduce a sharp end or point upon the formed whisker, and which Willhold such end accurately in alignment with the center of the anodewithin a tolerance of about .005 of an inch.

A further object of the invention is to provide a method of the abovementioned character for performing the steps accurately and quickly.

Other objects and advantages of the invention will be apparent duringthe course of the following description:

In the accompanying drawings forming a part of this application and inwhich like numerals are employed to designate like parts throughout thesame,

Figure l is a plan view, partly diagrammatic of apparatus used in thepractice of my method,

Figure 2 is a transverse section taken on line 2-2 of Figure 1,

Figure 3 is a transverse section taken on line 33 of Figure 1,

Figure 4 is a horizontal section taken on line 4-4 of Figure 6,

Figure 5 is a plan view of the lower forming jaw,

. Figure 6 is a vertical section taken on line 6-6 of Figure 1, partsbroken away, showing the position of the various apparatus elements,prior to the first step in the method,

Figure 7 is a similar view, showing the position of the elements forperforming the first step in the method,

Figure 8 is a similar view, showing the position of the elements inperforming the third step of the method,

Figure 9 is a similar view, showing the position of the elements whenperforming the fourth step in the method,

Figure 10 is a similar view, showing the position of the elements whenperforming the fifth or final step of the method.

Figure 11 is a perspective view of the finished product, and,

Figure 12 is a side elevation of the finished product.

The machine to be used in the practice of the method comprises ahorizontal turret 10, which is indexed by a vertical shaft ll, turned byany suitable means. The turret It may be turned clockwise, as shown inFigure l. The turret It? is provided upon its upper face with aplurality of spaced radial anode holding pockets or recesses 12, formedin blocks 13 rigidly secured to the turret. The turret is provided withradial slots 13', which lead into the recesses 12, Figure 3. The pocketsor recesses 12 are adapted to receive and hold cylindrical pins oranodes 14, having reduced extensions 14'. The anodes 14 and theextensions 14' are cylindrical and are preferably formed of nickel.Welded to one end of each "ice anode is a lead wire 15, arranged at thecenter of the anode. The wire 15 is welded to the anode prior to theintroduction of the anode into the pocket 12, and the welding of thewire to the anode forms no part of the present invention. The turret 10is indexed to bring each anode held within the pocket 12 to a selectedposition P, at which the several steps of the method are practiced.

The numeral 16 designates a stationary guide arranged near the turret10. This stationary guide has a recess 17 formed therein, Figure 2,which is undercut to receive a slide 17. The slide moves in a fixedhorizontal path which isradial with respect to the turret 10. Arrangedabove the slide 17 and rigidly secured thereto by screws 18 or the like,is a stationary jaw 19, having a lower face 26, spaced slightly from theslide 17. This lower face has a longitudinal groove 21 formed thereinwhich receives a wire 22, fed from a spool 22. The wire 22 is preferablyformed of tungsten, silver, gold, platinum or the like.

Arranged beneath the stationary jaw 19 is a movable jaw 23 operatingwithin a slot 24 formed in the slide 17, and pivotally mounted upon theslide by a pin 23', to swing in a vertical plane. The jaw 23 has anextension 24 at its free end, movable into the longitudinal groove 21,for clamping engagement with the wire 22. Rigidly connected with the jaw23 is a depending arm 25, provided with a horizontal extension 26,carrying a stop screw 27 to contact with the slide 17, for controllingthe extent of opening movement of the jaw 23. The arm 25 is pivotallyconnected at 28 with a link 29, which is movable horizontally inopposite directions and which is,

shifted by any suitable means.

it might be stated at this point that the wire 22 remains permanentlywithin the groove 21, during the operation of the apparatus in thepractice of the method, and when the link 29 is moved forwardly the wireis clamped within the groove 21 and moved forwardly. The wire 22original 1y extends beyond the jaws 19 and 23 for a short distance, suchas about one sixteenth of an inch, although this may vary. The forwardend of the wire will then be brought into overlapping relation with thereduced portion 14 of the anode.

The numeral 30 designates a welding electrode, which is moved verticallyby any suitable means and which is spring pressed downwardly. Rigidlyconnected with the electrode 30 to move therewith is a vertical presserplate or web 30', which is radial with respect to the turret It) toenter the top of the pocket or recess 12. The electrode 30 is connectedwith one side of a welding circuit and is thoroughly insulated from theturret and all other parts of the machine, the opposite side of whichcircuit is elelectrically connected with the turret 10, each block 13and the anode held therein.

The apparatus comprises means for forming a U- shaped portion in thewire, between the anode 14 and the jaws 19 and 23. The forming means isarranged between the turret l0 and jaws 19 and 23 and comprises avertically movable jaw 32, having a recess 33 forming upstandingportions 33 and 34'. The forming means further comprises a verticallymovable jaw 34, arranged near the electrode 30 and movable independentlyof the electrode. The jaw 34 has a depending extension 35 to enter therecess 33 of the jaw 32. The jaw 32 has a vertical presser plate or web35' rigidly secured thereto, which is radial with respect to the turretit? to enter the slot 13'. The extension 34 has a horizontal shoulder 37and the jaw 34 has a horizontal shoulder 38.

The lower forming jaw 32 has a vertical face 40, Figure 5, which ishorizontally inclined and the upper jaw 34, Figure 4, has a verticalface 41 which is horizontally inclined. The faces 40 and 41ers inalignment.

Slidably mounted upon the upper jaw 34 is a blade or cutter 32 and thisblade or cutter is horizontally inclined and will slidably contact withthe faces 41 and 4d. The blade 42 has a lower cutting edge 43. The blade42 has a horizontal extension 45, engaging a coil spring 46', engagingthe top of the upper jaw 34. In operation, the jaw 34 and blade 42 maymove downwardly as a unit, and after the forming action is completed,the blade 42 then moves downwardly with respect to the jaw 3 to severthe wire, the spring 46 being compressed.

Figure 6 shows the relative positions of the dilferent elements of theapparatus, prior to the starting of the method. The jaw 34 is raised,electrode 30 is raised, jaw 32 is lowered and jaws 19 and 23 are in therear position and jaw 23 is in the open position. The wire 22 ispermanently retained within the groove 21, and when the turret It} isindexed, the anode 14 is brought in alignment with the wire 22, and theupper face of the reduced extension 1% will be at the elevation of or inthe line of feed of the wire. The turret id is now stationary, and thelink- 29 is moved forwardly, swinging jaw 23 upon its pivot 23',clamping the wire between the jaws 19 and 23. The wire now extendsbeyond the jaws 19 and 23 for a suitable distance which may be about asixteenth of an inch although this length may vary. With the wireclamped to the jaws, the further forward movement of the link 29 movesthe slide 17 forwardly and the jaws 19 and 23 move forwardly andposition the free end of the wire over the reduced extension 14. Thisstep is shown pressed downwardly now moves downwardly and the electrodefirmly presses the wire 22 against the extension 14, while the presserplate 30' bears against the anode 14, holding it against movement. Theslide 17 remains stationary at the forward position, until the weldingis completed. The welding circuit is now closed for the proper weldingtime, and opened by the timing means at the end of the welding time, andthe wire 22 is securely welded to the reduced extension 14'. Theelectrode 30 remains in the lowered position and continues to bearagainst the wire 22, and the link 29 is now moved rearwardly from theturret. As soon as the link 29 moves rearwardly, the jaw 23 is shiftedto the opened position and the jaws T9 and 23 then slidably engage thewire, and further rearward movement of the slide 17 is affected by thecontinued rearward movement of the link 29. When the slide 17 reachesthe end of its rearward movement, it is held stationary, at thisposition, until the starting of the next cycle of operation. The jaw 23now remains in the opened position. This step is illustrated in Figure 8of the drawings.

The lower forming jaw 32 is now moved upwardly and the upstandingportion 33 first contacts with the wire and the presser plate 35contacts with the anode and the further upward movement of the lowerforming jaw is continued so that the anode 14 is raised until its centerline L is in alignment with the line of feed of the wire. The electrodeand upper presser plate 30 which are down wardly spring pressed areforced upwardly but these parts remain in engagement with the work. Thisstep is shown in Figure 9 of the drawings.

The lower forming jaw 32 remains in the raised position, Figure 9 andFigure 10 and the upper forming jaw 34 is now moved downwardly to thelowermost position, Figure 10. The extension 35 enters the recess 33 andthe U-shaped portion P is formed in the wire. The shoulders 37 and 33,Figure 10 form a horizontal extension E in the wire, and this extensionis in alignment with the center line L of the anode, and is held in suchalignment within a tolerance of .005 of an inch. The groove 21 issufficiently wide to slidably receive the wire, and accurately holds itagainst horizontal displacement and in a true line of feed. When theupper forming jaw 34 is moved downwardly to form the U-shaped portion,the wire is payed out from the spool 22, since it now slidably engagesthejaws 19 and 23. The upper forming jaw is firm-1y pressed toward thelower forming jaw, and after the U-shaped portion P has been formed, theblade 42 is moved downwardly with respect to the jaw 34, and the wire issevered, at an incline of 45, forming a sharp point on the extension E.

The slide having been returned to the rear position, the upper formingjaw 34 is returned to the raised position, the blade 42 to the raisedposition with respect to the jaw 34 and the forming jaw 32 to thelowered position, and the finished product will be lowered and held inthe pocket12, and may now be removed from this pocket, since the variousparts of the apparatus again assume the position shown in Figure 6. Thiscompletes the cycle of operation.

it is to be understood that the form of my invention herewith shown anddescribed are to be taken as preferred embodiment of the same, and thatchanges may be made in the steps of the method, and in the order of suchsteps, without departing from the spirit of the invention or the scopeof the sub-joined claims.

Having thus described my invention, what I claim is:

l. The method of forming a diode element, compris ing holding an anodeelement in a selected position, moving the wire longitudinally in afixed line of feed toward the anode element and bringing the wire intocontact with the anode element and pressing the wire against the anodeelement and welding the wire to the anode element to form a weldedjoint, forming a laterally extending portion in said wire and paying outthe wire from its end remote from the welded joint, then severing thewire at a point remote from welded joint and holding the severed end ofthe laterally extending portion in substantial alignment with the centerof the anode element.

2. The method of forming a diode element, comprising feeding a wire inone direction in a fixed line, supporting an anode in a position so thatthe wire has its end brought into overlapping relation with a part ofthe anode while the center of the anode is out of alignment with theline of feed of the wire, pressing the wire against the anode andwelding the wire to the anode, paying out the wire toward the point ofwelding and forming a laterally extending portion in the wire and anextension on said laterally extending portion, holding said extension inthe line of feed of the wire, shifting the anode so that its center isin substantial alignment with the line of feed of the wire, and thensevering the extension upon an inclination.

3. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axis substantiallyhorizontal in a selected position, moving a wire longitudinally in a substantially horizontal line of feed which extends longitudinally of saidcentral longitudinal axis and into exterior overlapping relation with aportion of said anode element which is laterally spaced from saidcentral longitudinal axis, then stopping the feeding of the wire andreleasing the wire so that its rear portion is free to pay out forwardlytoward the anode element, welding the wire to said portion of the anodeelement, moving upper and lower forming jaws into engagement with saidwire at a position rearwardly of the welding point and thereby forming agenerally U-shaped portion in said wire and an extension upon one sideof said U-shaped portion while paying out the wire in said forwarddirection, said forming serving to hold said extension against movement,shifting the anode element vertically to bring its central longitudinalaxis in alignment with said extension, severing the extension while heldby the forming jaws, and separating the generally U-shaped portion fromthe forming jaws.

4. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axi in a selectedposition, moving a wire in a longitudinal line of feed which extendslongitudinally of said central longitudinal axis and forwardly towardthe anode element to bring the forward end of the wire in exterioroverlapping relation with a portion of said anode element which isspaced laterally from said central longitudinal axis, then stopping thefeeding of the wire and releasing the wire so that its rear portion isfree to pay out forwardly toward the anode element, then welding thewire to the anode element, then moving forming jaws into engagement withsaid wire at a position rearwardly of the welding point andsimultaneously shifting the anode element to bring said centrallongitudinal axis int-o alignment with said line of feed, said formingjaws forming .a generally U-shaped portion in said wire and an extensionupon one side of said generally U- shaped portion, said forming jawsholding said extension in alignment with said central longitudinal axis,severing said extension while being held, and then releasing the formedwire.

5. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axis in a selectedposition, moving a wire longitudinally in a line of feed which extendslongitudinally of said central longitudinal axis and thereby bringingthe forward end of the wire into exterior overlapping relation with aportion of the anode element which is spaced laterally from said centrallongitudinal axis, then stopping the feeding of the wire and releasingthe wire so that its rear portion is free to pay out forwardly towardsaid anode element, welding the wire to the anode element, then forminga laterally extending loop in said wire and an extension upon one sideof said loop while paying out the wire in a forwardly direction, saidforming serving to locate the extension in said line of feed, shiftingthe anode element laterally to bring its central longitudinal axi inalignment with said line of feed, and then severing said extension.

6. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axis in a selectedposition, moving a wire longitudinally in a line of feed which extendslongitudinally of said central longitudinal axis and bringing the wirein exterior overlapping relation with the anode at a point space-dlaterally from said central longitudinal axis, welding the wire to theanode element, then paying out the wire toward the point of welding andforming a laterally extending loop in said wire and an extension uponone side of said loop, arranging the extension in alignment with saidcentral longitudinal axis, and then severing said extension.

7. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axis in a selectedposition, moving a wire longitudinally in a line of feed which extendslongitudinally of said central longitudinal axis and into exterioroverlapping relation with a portion of said anode element which islaterally spaced from said central longitudinal axis, stopping thefeeding of the wire and releasing the wire so that its rear portion maypay out in a forward direction, the side of the wire remote from theanode element being uncovered, welding the wire to said portion of theanode element, then shifting the anode element laterally with respect tothe line of feed, forming a single laterally extending loop only in saidwire rearwardly of the point of welding and an extension upon the sideof said loop remote from the anode element while paying out the wire ina forward direction, said forming also holding the extension andlocating said extension in alignment with said central longitudinalaxis, severing the extension while being held, and then releasing theformed wire.

8. The method of forming a diode element, comprising holding anelongated anode element having a central longitudinal axis in a selectedposition, moving a wire longitudinally in a line of feed which extendslongitudinally of said central longitudinal axis and into overlappingrelation with a portion of said anode element which is laterally spacedfrom said central longitudinal axis, the wire being arranged exteriorlyof said portion, arranging forming jaws upon opposite sides of andspaced from the wire when the forming jaws are in the open position sothat the wire is fed between the forming jaws, stopping the feeding ofthe wire and releasing the wire so that its rear portion is free to payout in a forward direction, welding the wire to said portion of theanode element, then effecting a relative lateral movement between theanode element and the line of feeding to bring said central longitudinalaxis in alignment with said line of feeding, then moving the formingjaws inwardly into engagement with said wire and thereby forming alaterally extending loop and an extension upon one side of said loopwhile paying out the wire in a forwardly direction, said forming alsolocating said extension in alignment with the line of feed and saidcentral longitudinal axis, severing the extension while being held bythe forming jaws, and then separating the formed wire from said formingjaws.

9. The method of forming a diode element, comprising holding an anodeelement at a selected position, feeding a wire toward the anode elementto a point which is spaced laterally from the center of the anodeelement to cause the free end of the wire to be arranged near andexteriorly of the anode element and overlapping the anode element,welding the wire to the anode element, paying out the wire toward thewelding point and forming the wire at a portion thereof rearwardly ofthe welding point and after the welding to provide a single laterallyextending loop only and an extension at one side of the loop and holdingthe formed parts after the forming action, shifting the anode element sothat its center is brought into alignment with said extension, severingthe wire at the extension after the forming action and while the formedparts are being held, and then releasing: .the anode element and formedparts for removal.

10. A method of forming a diode element, comprising supporting an anodeelement having a central longitudinal axis in a selected position,feeding a wide longitudinally toward the anode element and arranging theforward end of the wire in exterior overlapping relation with a portionof the anode element, the wire then extending longitudinally of theanode element and spaced laterally from its central longitudinal axis,engaging said forward end of the wire with a clamping welding electrodeand welding said forward end to the anode element and continuing toclamp the forward end with the clampingelectrode, bodily shifting theanode element laterally with the wire welded thereto so that the centrallongitudinal axis of the anode element is aligned with the line of feedof the wire, moving forming jaws into engagement with the wirerearwardly of the clamping welding electrode and paying out the wiretoward the welding electrode to form in the wire a laterally extendingloop and a longitudinal extension upon the side of the loop remote fromsaid electrode, holding the longitudinal extension in accurate alignmentwith the central longitudinal axis of the anode element, and thensevering said longitudinal extension close to corresponding sides of thejaws and while it is held by the jaws to complete the diode element.

11. A method of forming a diode element comprising supporting an anodeelement having a central longitudinal axis in a selected position,feeding a wire longitudinally of said anode element and spaced laterallyfrom said central longitudinal axis toward the anode element andarranging the forward end of the wire in exterior overlapping relationwith a portion of the anode element, clamping said forward end of thewire to the anode element and welding the wire to the anode element andcontinuing the clamping action after welding, bodily shifting the anodeelement with the wire welded and clamped thereto laterally in adirection for causing the central longitudinal axis of the anode elementto be aligned with the line of feed of the wire, engaging the wire at apoint paced f m ts po nt at l n an l mp n Poin and nay nsf u he i e toard the ano emen d forming in the wire a generally U-shaped lateral loopand a longitudinal extension upon the side of the loop remote from thewelding and clamping point and simultaneously holding the formed loopand extension to position the extension in accurate alignment with thecentral longitudinal axis of the anode element, and then severing thelongitudinal extension while it is being held throughout its entirelength to complete the diode element.

12. A method of forming a diode element, comprising supporting an anodeelement having a central longitudinal axis in a selected position,moving a wire longitudinally toward the anode element and arranging theforward end of the wire adjacent a side of a portion of the anodeelement, the wire then extending longitudinally of the anode element andspaced laterally from its central longitudinal axis, Welding the wire tothe anode element, moving forming jaws into engagement with the wirerearwardly of its point of welding to the anode element and paying outthe wire toward the point of welding to form in the wire a laterallyextending loop including a side arranged next to the anode element and asecond side arranged remote from said anode element, severing the secondside from the wire at a point remote from the anode element to providesaid second side with a free end, and accurately positioning said freeend in axial alignment with the central longitudinal axis of the anodeelement.

1 A m t c o forming a d o e clemen ompris n supporting an elongatedanode element having a. central longitudinal axis in a selectedposition, feeding a wire longitudinally toward one end portion of theanode element, welding the forward end of the wire to said end portionof the anode element, efiecting a relative closing movement betweenforming jaws so that they engage with opposite sides of the wirerearwardly of its point of Welding to the anode element and paying outthe wire toward the point of welding and thereby forming in the wire alaterally extending loop and a longitudinal extension upon one side ofthe loop, accurately aligning said longitudinal extension axially withsaid central longitudinal axis of the anode element, and then severingsaid longitudinal extension close to corresponding faces of the formiaws while i jaws continue to hold said longitudinal ':..tension in :nnment with said central longitudinal axis.

References Cited in the file of this patent UNITED STATES PATENTS

